Try going for the CCA races ( Championship Cup Series ). It's $40 for Fri. - Sun. for paddock and all other access.
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It's the same race org. I'm involved with as a U.S. Marshall. MAARC is the group that runs the corner workers for CCS events.
If you want, I could contact them and see if you could corner work for the event. If you worked the event you could also camp at the track. Spectators aren't allowed to.